Because he's not, A commander in military terms is above the rank of major.
- In the codex, Major/Captain ranks above (Lieutenant)Commander.
- 2nd Lieutenant
- 1st Lieutenant
- Staff Lieutenant
- Lieutenant Commander
- Staff Commander
- Rear Admiral/General
- Fleet Admiral
Maybe it's because shepard was a spectre
Ok so this might not be relevant, but in the US Navy, the commander of the ship always is the highest authority on thier ship; seconded by their executive officer. In ME1 it was the CO Anderson and his XO Shepard, before the Spectre ceremony. Afterwards, it was CO Shepard, XO Pressely, and in ME2 it was CO Shepard, XO Miranda.
Usually in this case, the Captains are the commanders of the ship, all answer to them. However, since Shepard never reached Captain, he is still in command of the Normandy(s). Also note in ME2, at before Tali's trial, Shala Raan tells Shepard that he commands the Normandy, and is responsible for the lives aboard it. Thunder
Its probably a mix of Spectre authority, Shepard's captaincy of the Normandy, and Kaiden's alliegence to Shepard after their exploits together. Also, by the time Kaiden rejoins the Normandy, he is himself a Spectre, and they do occasionally work in teams. Presumably one has to be in overall command of any mission, and in this case, Shepard would be. AdmiralPoel
Also because Shepard has been put in charge of the War against the reapers, like said above; is in command of the ship and probably because Shepard has a ton more experince then Kaidan.
Also, in ME3 after the Arcturus Station is broken, Admiral Hackett is in charge of the entire Alliance and its ships. I don't believe he ever reached promotion to Fleet Admiral, but either way, he is the highest ranking officer left; just like Balak is the highest ranking officer in the Hegemony, Victus was next in line for Primarch...etc. The Reaper war left a lot of unwilling, but extremely capable people in charge of their respective species (except the Salarians, their just fools) Thunder
I always like it when this question comes up, and I always have the same answer: Because he's the Goddamn Shepard. Shepard is its own rank that supercedes Admiral. Plus, in the U.S. military, a 2nd Lieutenant technically outranks the Sergeant Major, but good luck to any wet-behind-the-ears academy graduate that actually tries to order the Sergeant Major around! Hahahaha. RShepard227
^That's because of the authority involved, though. A Sergeant Major may be a lower rank, but he or she is usually second-in-command of a battalion, while a 2ndLt is only in command of a platoon.
^also a sgt usually has had a more time in active service than the average 2nd lieutenant who has just come out of Sandhurst (in the case of the British) or its equivalent
^^ That'd be West Point for the Americans, but I see your point. RShepard227
Well, just after Shepard's reinstatement into the Alliance the Council either returns or upholds their Spectre status, which would likely supersede any military rank; since Spectres have no ranking structure, a likely setup is that junior Spectres (like Kaidan) tend to defer to senior Spectre agents (like Shepard). There is also the matter of the emergency powers granted to Shepard by Admiral Hackett shortly after the former's return to active duty, permitting them to assume command of the Normandy and take any military or diplomatic action necessary to defeat the Reapers; Hackett only steps in to offer advice and keep tabs on Shepard's progress. Terminator-HIX
Shepard is a Navy Commander, Alenko is Major of the biotics division (think US Army Major). He is one whole rank below Shepard. -anon
^Not the same rank structure. Besides, Shepard is a Lieutenant Commander, which is equal to Major (in the U.S.) military anyway.
Like the anon before me said, Shepard is in the Navy. All throughout Mass Effect 3, Shepard is stated that he is in the Alliance Navy. Seems like a contradiction (Navy and Space).
Not only is Shepard the senior Spectre officer, but she is also in command of the Normandy. While on board her ship, traditionally Kaidan would defer to her.
All personnel aboard the Normandy are subordinate to Shepard in his mission. It is his command, until relieved. Byrdology
I'd just ignore what their respective ranks are, and ignore Spectre authority as of secondary importance. Shepard is in charge because Shepard is Hackett's (and Udina's, before the coup) direct representative in the field. Being the admiral's adjutant outstrips being a random major on detatched duty.
^ Besides that, who'd want to have Kaidan ordering them around the whole time. That wouldn't make a very fun game... Terminator-HIX
Because they're both Spectres. Rank doesn't matter. However, Shepard has been a Spectre longer than Kaidan, which means he/she has seniority.
^The rank of Major is actually equal to the rank of Lieutenant Commander, Shepard being a Commander (equal to Lieutenant Colonel) still has authority. Ashley defers to Shepard as well, her rank being LC. Captain as a Navy rank ist equal to the Army rank of Colonel. Admittedly it can be quite confusing but one always has to keep Army and Navy ranks apart. For example Kirrahe, a Captain in the first game, a Major in the third due to a promotion. This would be an Army rank.
^ At the create a character screen, it shows Shep's rank as CDR, not an LC anymore. It would seem as though he has been promoted to a full commander, or Staff Commander, in terms of the game. In Army Ranking, he'd be a full bird Colonel. While Major does outrank him in Mass Effect's structure in the Alliance, he is in command of the ship and the Major is basically just assigned to his ship. Whoever has command of the ship has final authority. He's basically the XO like Pressley was. As for Kirrahe, that's another species all together and their military ranks are different.
Kaidan is a marine (as evidenced in ME1) as is Shepard (the N7 program is the super elite marines, after all). I believe that Shepard referring to himself as "Alliance Navy" is because the marines are a subsidary of the Alliance Navy. I think that Kaidan (and Ashley, to a lesser extent) defer command to Shepard because of their immense respect for them even though they are at least the same rank as him. Shepard probably wasn't due for promotion to Admiral any time soon (although he did full well deserve it) because he was dead for 2 years and then joined up with a bunch of terrorists. Doesn't exactly look good to the promotions board. Oktenko (talk)
^I have a feeling that the game designers misunderstood Military Ranks due to the inconsistent use between the navy and the army/airforce uses. Just a hunch though.